Attachment for knitting machines



April 1941- w. E. GREENLEE 2,239,488

ATTACHMENT FOR KNITTING MACHINES Filed July 21, 1938 h InzJerzZor: 3 L: Mllzamlffi'reenleg 8 62 64 m :2; gammy Patented Apr. 22, 1941 ATTACHMENT FOR. KNITTING MACHINES William E. Greenlee, Philadelphia, Pa., assignor of one-half to'Warren P. Grlfliths, Trenton,

Application July 21, 1938, Serial No. 220,423

9 Claims.

This invention relates to attachments for full fashioned knitting machines and more particularly to a safety attachment which may be applied and knitting must set in alternately and at proper intervals to give the leg the desired shape. A chain motion is employed for accomplishing this automatically but if, for any reason, the narrowing mechanism is operated twice in succession, and so that there is no knitting operation interposed between the narrowing operations, injury to the needles or to the narrowing points or both will occur and the fabric which is being knitted is either damaged or spoiled.

It is an object therefore of the present invention to provide an attachment for knitting machines which will prevent successive narrowing or picoting operations unless and until a course of knitting has been interposed therebetween.

It is a further object of the present invention to provide an attachment for knitting machines which will effectively reduce the likelihood of injury to the needles of the knitting machine.

It is a further object of the present invention to provide an attachment for knitting machines which will reduce the likelihood of damage or injury to the fabric being knitted and thus increase the yield of fabric free from spoils or seconds.

Other objects of the invention will appear from the annexed specification and claims.

The nature and characteristic features of the invention will be more readily understood from the following description, taken in connection with the accompanying drawing forming part hereof, in which:

Figure 1 is a fragmentary vertical sectional view of a portion of a knitting machine with the attachment of the present invention applied thereto;

Fig. 2 is a fragmentary plan view of the apparatus shown in Fig. 1;

Fig. 3 is an elevational view of a control arm forming part of the attachment illustrated in Figs. 1 and 2; and

Fig. 4 is a fragmentary plan view of a knitting machine showing a modified form of the attachment; and t Fig. 5 is a fragmentary sectional view on the line 55 of Fig. 2.

It will, of course, be understood that the description and drawing herein contained are illustrative merely, and that various modifications and changes may be made in the structure disclosed without departing from the spirit of the invention.

Referring more particularly to the drawing, the safety attachment of the present invention is there illustrated in connection with a machine of the Reading type, although, it will, of course, be evident that the attachment of the present invention may be used on other types of flat knitting machines where the same or a similar character of control of the loop transfer operations such as narrowing or picoting is employed, and changes may be made for this purpose.

The front beam of the knitting machine is shown at ill and the back beam at ll. The cam shaft of the machine at [2 has mounted thereon cams I3 and M for effecting a lateral or longitudinal shifting of the cam shaft l2 in the customary manner, in one direction and to the right as illustratedin knitting cams (not shown) are moved out of action and the narrowing or picoting cams (not shown) are moved into action, and upon lateral or longitudinal shifting of the cam shaft H to its initial position, the narrowing or picoting cams are moved out of action and the knitting cams moved into action. This movement of the cam shaft I2 is effected by the chain motion l5 which may be of any well known type. The chain motion I5 is preferably carried by the front rail 10.

The chain motion l5 as illustrated preferably includes a pattern chain l6 for determining the particular and separated courses in which a narrowing or picoting operation is to take place as heretofore indicated by laterally shifting the position of the cam shaft l2. The pattern chain I6 is mounted on a chain sprocket ll.

A pin or button [8 is provided on the pattern chain [6 where a narrowing operation is desired and in the form of chain motion mechanism illustrated this button l8 contacts a projection IS on a lever 20 to lift the lever 20 and thereby swing.

which is weighted as at 25, and a locking device is provided which is intended to prevent the lever 24 from being shifted to move the cam shaft I2 except as desired.

Upon movement of the lever 24, a stud shaft roller or shogging truck .26 carried thereon is permitted to move and is moved by a spring 21 connected thereto to a position such that it contacts the lateral projection 28 of the cam I3. The contact of the roller 26 with the projection 26 of the cam I3 forces the cam I3 and the cam shaft I2 to the right for bringing the narrowing or picoting mechanism into action.

The locking device includes a small shoulder at 29 on the arm 2I which engages the lateral projection 23 on the lever 24 and is intended to prevent the lever 24 from being shifted to move the cam shaft I2 until the lever 24 is released by the chain motion. The release is effected through a ratchet pawl 36 which is operated through a lever 3I and a supplementary cam 32 on the cam I4 and works in the ratchet of the chain sprocket II so as to cause the chain sprocket to rotate the space of one tooth for each revolution of the cam shaft I2.

When one of the buttons I8 comes under the projection I6 of the lever", it will lift this lever 26 thereby swinging the lever and releasing the projection 26 and the lever 24.

During the revolution where the locking device is in action the pawl 36 has moved the sprocket II the space of one tooth thus moving the button I8 from its position beneath the projection I9.

After the narrowing operation has taken place, the supplementary cam 33 which is secured to the cam I3 moves against the stud shaft roller 34, pushes the roller 34 back and moves the arm 24 and the roller 26 so that the roller 26 is brought to a position so that it may engage with the lateral projection 35 of the cam I4 and operate to shift the cam shaft I2 back to its original position.

Upon the engagement of the lever 2I with the lateral projection 29 and if the engagement is effective the lever 24 is held in position until released by the next button I8 brought under the projection IS. The chain I6 may also be provided with a number of high buttons 36 which contact with a projection 31 of the ratchet pawl 36 to disengage the ratchet 38 of the sprocket wheel I! and consequently stop the travel of the chain I6. The narrowing is thus intended to be stopped automatically without requiring the attention of the knitter. When it becomes necessary to start it again, the operator may, by actuation of a manually operable lever 36, cause a ratchet pawl (not shown) to engage the teeth of the ratchet wheel 36 of the chain sprocket l1 to rotate the latter for the space of one tooth and remove the high button 36 from beneath the projection 31 and bring the pawl 36 into operation again.

The foregoing structure represents and is typical of the chain motions with which diniculty has been encountered and which is overcome by the attachment hereinafter described.

The safety attachment of the present invention preferably includes a base or frame member 56 which is adapted to be secured, in any desired manner, to the back beam II of the knitting machine. The frame member 56 permits the installation of the attachment on knitting machines which are now in use.

The frame member 66 has a lever arm thereon, pivotally mounted as at 62, and the length of the lever arm 6| is preferably made adjustable, such as by a suitable bolt and slot connection 63 between the constituent portions of the lever arm 5i. The end portion of the lever arm 6| is preferably provided with a roller- 54 on the end thereof for engagement with the end face of the boss I3 of the cam I3. A collar 55 is preferably mounted on the shaft I2 to insure a positive actuation of the lever arm 5| in accordance with the positioning of the cam shaft l2.

In the modified form of lever arm 5| shown in Fig. 4 the end portion 66 of the arm 6| is shaped as at 61 for contact with the end face of the boss I3, and a spring 66 connected to the lever arm 5|" and'to the frame member 66 is provided for holding the end portion 61 of the lever 6| in contact with the end face of the boss I3'-.

The lever arm 5| has secured thereto for movement therewith a control arm 66 which has a high portion 6|, a lowv portion 62 and an inclined connecting portion 63 therebetween for purposes hereinafter referred to.

The frame member 66 also has pivotally mounted thereon for vertical movement a control rod 64, the mounting preferably including a bolt 65 so that the rod 64 may be adjusted with the forward end thereof at the desired position with respect to the roller 26.

The control rod 64 extends forwardly between the cams I3 and I4 for engagement as hereinafter more fully referred to with the rear face of the stud shaft roller 26. The control rod 64 rests on and is in engagement with the control arm 66 and is raised or lowered by the control arm 66 in accordance with the positioning of the lever 5|.

When the stud shaft roller 26 has been brought into contact with the cam I3 by one of the buttons I6 on the chain I6, the cam shaft I2 is moved to the right and in so doing, the hub I3 of the cam I3 is likewise moved to the right and carrieswith it the lever 5| and the control arm 66 mounted thereon provides a controlled support for the control rod 64. As the control arm 66 moves to the right the high portion 6| moves to a position so that it does not support the control rod 64 but the control rod 64 may rest upon the stud shaft roller 26. As the cam shaft I2 revolves, the cam member 33 is brought to a position so that it engages the roller 34 to move the lever 24 and the roller 26 thereon outwardly. As the roller 26 moves outwardly the control rod 64 will no longer be supported upon the roller 26 and will drop behind the roller 26. The control rod 64 upon dropping will be supported by the low portion 62 of the control arm 66. This occurs in the interval before the roller 26 has engaged the projection 36 on the left hand cam- I4 and before the roller 26 by such engagement has returned the cam shaft I2 to its initial position. The control rod 64 is then effective to hold the roller 26 in its forward position, in spite of any failure of the latching mechanism to hold the lever 24 in its forward position. The roller 26 is thus positively held in a position to contact the projection 35 on the cam I4 and return the shaft I2 to its initial position. Upon the return of the shaft I2 to its initial position another knitting operation will take place before the roller 26 can again move inwardly to bring about another narrowing operation.

Upon the return of the cam shaft I2 the lever arm to under the control of the movement of the cam shaft It returns to its initial position so that narrowingv or picoting operation this will be prevented by the attachment herein described.

Iclaim:

i. In a knitting machine having mechanism for controlling the loop transfer operations, said mechanism including a rotatable and longitudinally shiftable shaft having av cam mounted thereon and a member adapted to engage said cam to shift said cam shaft longitudinally, the combination therewith of auxiliary means actuated by the longitudinal movement of said shaft for preventing the longitudinal actuation of said shaft in the next succeeding revolution thereof.

2. In a knitting machine having mechanism for controlling the loop transfer operations, said mechanism including a rotatable and longitudinally shiftable shaft having a cam mounted thereon and a member adapted to engage said cam to shift said cam shaft longitudinally, the combination therewith of means for preventing the longitudinal actuation of said shaft in the next succeeding revolution thereof, said means including a holding member for holding said engaging member out of contact with said cam, and a control device for said holding member directly actuated by the longitudinal movement of said shaft.

3. In a knitting machine having mechanism for controlling the loop transferoperations, said mechanism including a rotatable and longitudinally shiftable shaft having a cam mounted thereon and a member adapted to engage said cam to shift said cam shaft longitudinally, the combination therewith of means for preventing the longitudinaLactuation of said shaft in the next succeeding revolution thereof, said means including a movable member for alternatively holding said engaging member out of contact with said cam and permitting engagement of said engaging member with said cam, and a control device for controlling the movement of said movable member, said control device belng directly actuated by the longitudinal movement of the shaft.

4. In a knitting machine having mechanism for controlling the loop transfer operations, said mechanism including a rotatable and longitudinally shiftable shaft having a cam mounted thereon and a member adapted to engage smd cam to shift said cam shaft longitudinally, the combination therewith of means for preventing the longitudinal actuation of said shaft in the next succeeding revolution thereof, said means including a member movable into and out of engagement with said engaging member for holding said engaging member out of contact with said cam, and a control device for controlling the movement of said movable member, said con- ,trol device including a portion movable with said cam shaft in its longitudinal movement. 5. In a knitting machine having mechanism for controlling the loop transfer operations, said mechanism including a rotatable and longitudinally shiftabie shafthaving a cam mounted thereon and a member adapted .to engage said cam to shift said cam shaft longitudinally, the combination therewith of means for preventing the iongitudinal actuation of said shaft in the next succeeding revolution thereof, said means including a member movable for engagement with said engaging member for holding said cam engaging member out of contact with said cam, and a device for controlling the movement of said movable member including a positioning dviceop erated by the longitudinal axial movement of said cam shaft.

6. In a knitting machine having mechanism for controlling the loop transfer operations, said mechanism including a rotatable and longitudinally shiftable shaft having a cam mounted thereon and a member adapted to engage said cam to shift said cam shaft longitudinally, the combination therewith of means for preventing the longitudinal actuation of said shaft in the next succeeding revolution thereof, said means including a member movable into and out of engagement with said cam engaging member for holding said cam engaging member out of contact with said cam, and a device for controlling the movement of said movable member, said control device having a portion movable with said cam shaft in its longitudinal movement, and a positioning device for said movable member actuated by the movement of said movable portion.

7. In a knitting machine having mechanism for controlling the loop transfer operations, said mechanism including a rotatable and longitudinally shiftable shaft having a, cam mounted thereon and a member adapted to engage said cam to shift said cam shaft longitudinally, the combination therewith of means for preventing the longitudinal actuation of said shaft in the. next succeeding revolution thereof, said means including a control lever operable by said shaft upon longitudinal movement of said shaft, a control arm connected to said lever, and a control rod, said control arm having portions for supporting said control rod at predetermined positions with respect to said engaging member in accordance with the positioning of said control arm.

8. In a knitting machine having mechanism for controlling the loop transfer operations, said mechanism including a rotatable and longitudinally shiftable shaft having a cam mounted thereon and a member adapted to engage said cam to shift said cam shaft longitudinally, the combination therewith of means for preventing the longitudinal actuation of said shaft in the next succeeding revolution thereof, said means including a control lever operable by longitudimember.

9. In a knitting machine having mechanism for controlling the loop transfer operations, said mechanism including a rotatable and longitudinally shiftable shaft having a cam mounted thereon and a member adapted to engage said cam to shift said cam shaft longitudinally, the combinationtherewi-th of means for preventing the longitudinal actuation of said shalt in the next succeeding revolution thereof, said means including a control lever operable by longitudinal moveengaging member in accordance with the position oi said control arm, and rod in onepoeition being in engagement with said cam ensuring member for preventing the engagement of said member with said cam and in another position being held out of engagement with said cam engaging member.

WILLIAM E. GREENLEE. 

